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1.
The human visual system is amenable to a number of adaptive processes; one such process, or collection of processes, is the adaptation to blur. Blur adaptation can be observed as an improvement in vision under degraded conditions, and these changes occur relatively rapidly following exposure to blur. The potential important future directions of this research area and the clinical implications of blur adaptation are discussed.  相似文献   
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The aim of this qualitative study was to explore the experiences of young persons using their hemiplegic hand in daily life activities following upper extremity surgery (UES). Ten persons, aged 12-24 years, were interviewed individually five to seven years after surgery. The analysis was guided by a comparative method. The findings show that the participants during this period had experienced changes which they related both to the treatment and to development. Data resolved into three main themes. Functional improvements are interwoven into daily life, the hand is easier to use and is used more, and changes in the appearance and in the internal feeling of the arm are of importance. This study reflects the patients' experiences of living with the outcome of UES and yields an important complement to objective, quantitative outcome studies.  相似文献   
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The effects of different thermal processes used to produce ready-to-eat cereals on the glycemic response to whole grain wheat were investigated in rats. The metabolic response to drum dried flour, which constitutes the major component in instant gruel and porridge, was also studied in healthy human subjects. Boiled flour was used for comparison. The degree of starch gelatinization and rate of starch hydrolysis in vitro were also measured. Incompletely gelatinized steam flaked and dry autoclaved products were digested more slowly in vitro and elicited lower glucose responses in rats compared with completely gelatinized drum dried, extrusion cooked or boiled samples. The initial glycemic response in rats was closely related to the rate of starch hydrolysis in the pepsin/alpha-amylase assay (r = 0.91, P less than 0.04). When pepsin was omitted, no significant correlation was obtained. The peak glucose, insulin and C-peptide responses in humans after breakfast meals of porridge prepared from drum dried flour and from boiled flour were similar, whereas the rate of depression of the glucose curve was more rapid after consuming drum dried porridge. It is concluded that the glycemic response to wheat products is affected by the processing conditions used. The more severe the processing conditions, the more rapid the digestion of starch.  相似文献   
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High serum fluoride (F-) in patients with chronic renal failure (CRF) and end-stage renal disease (ESRD) is associated with risk of renal osteodystrophy and other bone changes. This study was done to determine F- in normal healthy controls and patients with ESRD on haemodialysis (HD) or peritoneal dialysis (PD). Seventeen healthy controls (12 males, 5 females) and 39 ESRD patients on dialysis (17 males, 22 females) were recruited in the study in a community with 47.4 +/- 3.28 microM/l (range 44-51 microM/l) of F- content in drinking water. Control subjects showed a mean serum F- concentration of 1.08 +/- 0.350 microM/l. Males in control group showed slightly higher F- levels (1.15 +/- 0.334, range 0.55-1.9 microM/l) than females (0.92 +/- 0.370, range 0.6-1.5 microM/l). Mean serum F- concentration did not correlate significantly with age and sex among control subjects, whereas such correlation was observed in patients with ESRD on dialysis. Mean serum F- concentration was significantly higher in patients on dialysis (2.67 +/- 1.09, range 0.8-5.2 microM/l) than normal controls. When grouped according to sex, the mean serum F- concentration in males (3.05 +/- 1.04, range 1.8-5.2 microM/l) was significantly higher than females (2.38 +/- 1.08, range 0.8-5.2 microM/l). When patients were grouped according to age, it was observed that F- concentration was significantly higher in patients with age groups 21-70 (2.86 +/- 1.05) than those with age group 13-20 years (1.42 +/- 0.531). Thus F- concentration correlated with age and sex, being higher in males and above 20 years. Despite appreciable clearance of F- (39-90%) across the peritoneum, patients on CAPD showed higher serum F- concentration than those on HD (3.1 +/- 1.97 vs 2.5 +/- 1.137 microM/l). Of the total 39 patients on dialysis 39% had their serum F- concentration above 3.0 microM/l, posing the risk of renal osteodystrophy.   相似文献   
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In an effort to evaluate the relationship between the site of air-flow obstruction and rate of improvement with therapy, we studied 20 asthmatics with spirometry, before and after bronchodilator, using air and 80% helium-20% oxygen (He-O2). Studies were obtained on 3 consecutive days after hospital admission and approximately 18 days after discharge. Greater He-O2 response ([Vmax50(He-O2)--Vmax50(air)]/predicted Vmax50) X 100, was associated with: less cigarette consumption (p less than 0.02), lesser frequency of chronic productive cough (p less than 0.02), more symptom-free intervals (p less than 0.02), and greater frequency of allergic rhinitis (p less than 0.03). Patients with greater He-O2 response (Group 1) reached maximal improvement in air flow by Hospital Day 2, whereas those with a lesser He-O2 response (Group 2) continued to improve throughout the observation period. The Group 1 mean peak expiratory flow rate (PEFR) improved by 24% of predicted per day to maximum, which was significantly greater (p less than 0.025) than the 11% per day rate of improvement of Group 2. The He-O2 response remained relatively stable throughout the course of the study except for 3 patients who dramatically improved their response with therapy. A highly significant correlation, adjusted for regression to the mean, (r = 0.95, p less than 0.0001) was found between mean baseline percent predicted Vmax50 and the mean He-O2 response. After adjustment for regression to the mean, there was no significant relationship between the degree of prebronchodilator He-O2 response and increase in He-O2 response with bronchodilator.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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Metabolic adaptation of the chick embryo to chronic hypoxia   总被引:1,自引:0,他引:1  
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We report the isolation and partial genetic characterization of two equine strains of granulocytic Ehrlichia of the genogroup Ehrlichia phagocytophila. Frozen whole-blood samples from two Swedish horses with laboratory-verified granulocytic ehrlichiosis were inoculated into HL-60 cell cultures. Granulocytic Ehrlichia was isolated and propagated from both horses. DNA extracts from the respective strains were amplified by PCR using primers directed towards the 16S rRNA gene, the groESL heat shock operon gene, and the ank gene. The amplified gene fragments were sequenced and compared to known sequences in the GenBank database. With respect to the 16S rRNA gene, the groESL gene, and the ank gene, the DNA sequences of the two equine Ehrlichia isolates were identical to sequences found in isolates from clinical cases of granulocytic ehrlichiosis in humans and domestic animals in Sweden. However, compared to amplified DNA from an American Ehrlichia strain of the E. phagocytophila genogroup, differences were found in the groESL gene and ank gene sequences.  相似文献   
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